Conveyor system for elongated structures



Sept. 16, 1969 J, suozzo ET AL 3,467,223

CONVEYOR SYSTEM FOR ELONGATED STRUCTURES Filed Feb. 11, 1966 7Sheets-Sheet 1 A Y A as as BANK 2 M 6 CARS 6558 B'ANK F BANKQI To iecARs411050 l 6 72 MIEHQIMIE"? HHHI H l IIIIIIIIH HHI HIIIIHIIIIHIIH I I E 45"FLOOR-SlfY olaav LOWER FEEDER FEEDER 3 Lg E 1 %g IBANKGG' BANKG I lLag 4CARS 4CARS 'IHIIIIHHIHI HIHIIH MQIIPI VAIN FLOOR 1 LOAD IN DEX 1 asAT 'KY LOBBY 3? 8 O QF '4.- TRAFFIC ORIGINATING TRAFFIC ORIGINATING MAINFLOOR SKY LOBBY DIVISIONAL INDEX FTG. l.

J. SUOZZO ET AL CONVEYOR SYSTEM FOR ELONGATED STRUCTURES Filed Feb. 11,1966 Sept. 16, 1969 7 Sheets-Sheet 2 D B M T V 8% mm 0 B B W Z m w B D VB W m H R 2 4 E M B E 3 B 6 6 A G B 1W In AIIB a a H 5 5 B W W W l q B m6 W A m B B I. v a 2 2 M A Z. 84 w w m w w M l B D l S 6 B U M H TM M UB m B 8% B v I T L m n 7 0 Vu M H 6 7 Z L 2 D W X w E A R 4 l 2 3 L a z6 s M E KW 2 I F F 5 5 U D a T a s 6 M I m x O 4 HT. 5 m X w S 3 MW 103M 4 U H 1H $1M. M M L4 3 A FIG.2.

Sept. 16, 1969 J. suozzo ET L CONVEYOR SYSTEM FOR ELONGATED STRUCTURES 7Sheets-Sheet 6 Filed Feb. 11. 1966 32 5 3x9 Ee mmmwmw Eem Sept. 16, 1969J. suozzo ET AL 3,467,223

CONVEYOR SYSTEM FOR ELONGATED STRUCTURES Filed Feb. 11, 1966 7Sheets-Sheet 7 GREB RS eTs|\ 7% I &

Clock 3 FIG. IO. F|G.||.

WITNESSES J hINVSENTORS d o n uozzo on Henry C. Sovino.

ATTORNEY United States Patent 01 fice 3,467,223 Patented Sept. 16, 19693,467,223 CONVEYOR SYSTEM FOR ELONGATED STRUCTURES John Suozzo and HenryC. Savino, Hackensack, N.J.,

assignors to Westinghouse Electric Corporation, Pittsburgh, Pa., acorporation of Pennsylvania Filed Feb. 11, 1966, Ser. No. 526,813 Int.Cl. B66]: N36

US. Cl. 187-29 Claims ABSTRACT OF THE DISCLOSURE A tall building has alower first feeder or shuttle bank of elevators operating between abottom terminal or main floor and a transfer floor. The building has alocal second bank of elevators operating between the transfer floor andhigher floors to provide local service. A computer maintains a propernumber of feeder elevators in service, distributes feeder elevator carsbetween the bottom terminal and transfer floors, and coordinates arrivalof local and feeder elevator cars at the transfer floor. If pluralfeeder banks are employed the computer coordinates the service providedby such feeder banks.

This invention relates to a conveyor system for elongated structures andit has particular relation to such a system wherein vehicles, such aselevators, are divided into one or more feeder banks and one or morelocal banks which may be located on one side of a feeder bank or banks.

It has been previously proposed that elongated structures, such as tallbuildings, be provided with vehicle or elevator service operating in twostages. As applied to a tall building, the first stage includes a feederor shuttle bank for providing express service between a lower main floorsuch as a street floor and a transfer floor located at a high level ofthe building. A second stage includes one or more local banks ofelevators for providing elevator service between the transfer floor andhigher floors of the building. These banks operate independently of eachother. Although some time is lost in the transfer of passengers at thetransfer floor, the transfer of passengers between the main floor andthe transfer floor can be accomplished by a relatively small number ofexpress highspeed elevators. This results in a very large overall savingin the space required for elevator hoistways.

In accordance with the invention the banks of elevators in a bank arecoordinated to provide efiicient operation. In a preferred arrangement,trafiic information is supplied to computer equipment. This computerequipment assists in controlling the elevator system to:

(1) Maintain in service a proper number of feeder elevator cars tohandle the existing trafiic;

(2) Distribute the feeder elevator cars between the main floor and thetransfer floor for utmost efiiciency;

(3) Coordinate arrival of local and feeder elevator cars at the transferfloor; and

(4) Coordinate service provided by plural feeder banks if more than onesuch bank is employed.

It is therefore an object of the invention to provide an improvedelevator system for tall buildings.

It is another object of the invention to provide an improved elevatorsystem employing feeder and local banks of elevators wherein such banksare coordinated to operate at improved efliciency.

It is also an object of the invention to provide an improved elevatorsystem employing local and feeder elevator banks having a commontransfer floor for coordinating arrival of the elevator cars at thetransfer floor to assure improved efiiciency.

It is an additional object of the invention to provide an improvedelevator system for tall buildings wherein the operation of pluralfeeder banks of elevators is coordinated for improved efficiency.

Other objects of the invention will be apparent from the followingdescription taken in conjunction with the accompanying drawings in whichFIG. 1 is a schematic view with parts in block form representing anelevator system embodying the invention; and

FIGS. 2 to 11 (including FIG. 3A) are diagrammatic representations withcircuits shown in straight-line form of an elevator system embodying theinvention.

FIGURE 1 The invention may be applied to buildings having variousnumbers of floors and various floor arrangements. For illustrativepurposes a building having 72 floors is illustrated in FIG. 1. Thesefloors include a main floor which may be located at the street level anda transfer floor which is assumed to be located at the 41st floor. Thisfloor also may be referred to as a sky lobby. Elevator service for thefloors between the main floor and the sky lobby is provided by one ormore banks of lower building elevators LBE.

Passengers desirous of travelling between the main floor and a floorlocated above the 41st floor or sky lobby travel between the main floorand the sky lobby in elevators located in one or more feeder banks. Forillustrative purposes two feeder banks 0 and 00 are shown. The number offeeder banks and the number of cars in each of the banks depend ontrafiic requirements. For present purposes, it will be assumed that eachof the feeder banks has four elevator cars A, B, C and D.

For elevator service above the sky lobby, passengers employ elevatorslocated in one or more banks. Again the number of local banks and thenumber of elevators in each of the local banks depend on trafiicrequirements. For illustrative purposes it is assumed that four localbanks qb, 1, p2 and 3 are employed. Each of the local banks is assumedto have six elevators A, B, C, D, E and F. The bank of elevators s isassumed to serve the floors 41 to 50. The bank 1 serves the 41st floorand the floors 51 to 58. The elevator cars in this bank are arranged torun express between the 41st and 51st floors. In a similar manner, theelevator cars of the bank 2 serve the 41st and 59th to 65th floors.Finally the bank 3 provides local elevator service for the 41st floorand the floors 66 to 72.

In order to coordinate the elevators of the elevator system for optimumefficiency, computer equipment is provided which includes a load index0L1 and a divisional index BD'I. The load index repeatedly samples thesum of the loads of all of the cars in the feed bank 6 that leave boththe main floor and the sky lobby. Thus the load index may include apointer 0LIP which indicates on an associated scale whether the totalloading is light, moderate, heavy or very heavy. This load indexdetermines in part the number of elevators in each of the feeder banksto be kept in service. The load index further indicates when help isdesired from another feeder bank. The load index additionally indicateswhen its feeder bank has one or more elevators available to help anotherfeeder bank.

The division index indicates the difference in traffic originating atthe main floor and at the sky lobby. Thus the divisional index may havea pointer 0DIP which indicates on a scale associated therewith thenumber of cars allocated to the main floor and to the sky lobby. In

CB FIG. l, the pointer is in a central position indicating a balancedcondition wherein the elevator cars of the bank are evenly dividedbetween the main floor and the sky lobby. Positions of the pointerdisplaced in a clockwise direction from the position indicated in FIG.'1 indicates that more traffic originates at the sky lobby than at themain floor and assigns a preponderance of the elevator cars of the bank0 to the sky lobby. Conversely a position of the pointer displaced in acounterclockwise direction from the position indicated in FIG. 1indicates that a preponderance of the trafiic originates at the mainfloor and that a preponderance of the elevator cars of the bank 0 shouldbe assigned or allocated to the main floor. When the traffic in thefeeder bank is predominantly in the up direction the divisional indexalso may bias the local banks to send cars to the sky lobby.

'The computing equipment also senses when traffic in the local banks to1 53 predominantly is in the down direction. Under this circumstance,the feeder banks are biased to assign elevator cars to the sky lobby.

If trafiic requirements follow a reasonably definite pattern on a timebasis in repetitive cycles the computing equipment may take the form ofclock mechanism for assigning car allocations and biases on a timebasis. However, in a preferred embodiment of the invention, theallocations and biases are responsive directly to the traffic.

A system involving the invention now will be discussed in detail. Inorder to simplify the presentation of the invention it will be assumedthat each of the banks of elevators is similar to the bank disclosed inthe Santini and Suozzo Patent 2,740,495 which issued Apr. 3, 1956. Theconventions employed in the patent also will be employed here. Thus forthe bank the first floor of the system shown in the patent wouldcorrespond to the sky lobby. For the bank 1 of FIG. 1, no car callregistering buttons or relays and no floor call registering buttons orrelays would be required for a floor between the 41st and 51st floors.Similar comments apply for the bank 2 and 53 with respect to the floorswhich are not served by these banks.

The feeder bank 0 also is based on the system shown in aforesaid patent.FIGS 2, 3, 4, and reproduce certain components of the aforesaid patentwith changes which will be discussed below. Components of FIGS. 2, 3, 4and 5 which are similar to components of the aforesaid patent areidentified by the same reference characters. In some cases which will bementioned below, contacts are added to the relays which are shown in thepatent. For convenience, the following components common to theaforesaid patent and to the present FIGURES 2, 3, 4 and 5 are reproducedas follows:

DDown switch EInductor slowdown relay FInductor stopping relay G-Holdingrelay LT-Lower-terminal relay M-Running relay MGMotor-generator startingswitch NL-Lower-terminal next relay NT-Upper-terminal next relayRDoor-control relay S-Floor or corridor-call stopping relaySL-Lower-terminal start relay STUpper-terminal start relayTIUpper-terminal relay UUp switch V--Speed relay W--Up-direction relayX-Down-direction relay Z-Door-safety relay 11Electric Motor 13Tractionsheave 15-Brake 60-Motor-generator set 70T-Non-interference relay 4FIGURE 2 FIGURE 2 is similar to FIG. 3 of the aforesaid Santini et al.patent with the following exceptions:

In the patent the up switch U, the down switch D and the running relay Mfor the elevator A are controlled by three parallel circuits in part. Afirst one of these circuits, also shown in the present FIG. 2, includesin series make contacts LT1 of the lower-terminal relay (the main floorin the present case) and make contacts SL1 of the lowerterminal startrelay. Consequently, when the elevator car A is to start from the mainfloor the contacts LT1 and SL1 close to energize the up switch U and therunning relay M.

The second circuit, also shown in the present FIG. 2, includes in seriesthe make contacts TT1 of the upperterminal relay and the make contactsST1 of the upperterminal start relay. In the present case, the upperterminal is the sky lobby. Consequently, when the elevator car A is tostart down from the sky lobby the make contacts TT1 and ST1 close tocomplete an energizing circuit for the down switch D and the runningrelay M.

The third circuit employed in the patent was for the purpose ofinitiating starting of the elevator car A from floors intermediate thetwo terminals. Inasmuch as the elevator cars of the bank 0 run expressbetween the two terminal floors, the third circuit is not here requiredand has been deleted. Inasmuch as the sky lobby is the upper limit oftravel of the elevator car A the limit switch 63 is set to open as thecar in travelling up nears the sky lobby. The limit switch 64 is set toopen as the car A nears its lower limit of travel, in this case the mainfloor, at the end of a down trip.

As shown in the Santini et al. patent, the inductor slowdown relay E andthe inductor stopping relay F are energized by any one of a number ofcontacts for the purpose of initiating a slowdown and stopping operationof the elevator car A. In the present case, only the make contacts S1are required for initiating a slowdown and stopping operation. The otherinitiating contacts shown in the patent consequently are deleted.

The up direction relay W is energized through a series circuit whichincludes only the break contacts D6 and X2, and the limit switch 66. Thelimit switch 66 is set to open as the elevator car A on an up trip nearsthe sky lobby. The patent shows similar components.

The down direction relay X is energized through a circuit which includesin series only the break contacts U6 and W2, and the limit switch 67.The limit switch 67 is set to open as the elevator car A on a down tripnears the main floor.

Similar changes are made in the circuits of the other elevators of thebank 0 and are shown for the elevator B.

FIGURE 3 The present FIG. 3 is based on FIG. 4 of the aforesaid patent.However, inasmuch as the elevator cars of the feeder bank 0 shuttlebetween the main floor and the sky lobby the circuits have beenmaterially simplified.

During an up trip of the elevator car A the only stop is at the skylobby. For this reason, the only contact segment required in the f rowis the contact segment M1 for the sky lobby floor. This contact segmentM1 is connected to the bus L1 and is positioned to be engaged by thebrush fc as the elevator car A on an up trip ap-' proaches the slowdowndistance required for the sky lobby floor. When the floor stopping relayS is energized it initiates a slowdown and stopping operation of theelevator car A at the sky lobby in the same manner discussed in down andstopping distance for the main floor the brush hc engages the contactsegment I11 to complete an energizing circuit for the stopping relay S.This initiates a stopping of the elevator car A at the main floor in thesame manner discussed in the patent.

A car-call registering relay 41CR and its canceling coil 41CRN areprovided for the sky lobby and a carcall registering relay 1CR and itscanceling coil 1CRN are provided for the main floor. Each of theserelays is picked up when its associated car button is pressed and isdropped out when the elevator car A nears the corresponding floor in themanner described in the aforesaid patent.

In addition, a floor-call registering relay 41DR and its canceling coil41DRN are provided for registering a down floor call from the sky lobbyand a floor-call registering relay 1UR and its canceling coil 1URN areprovided for registering an up floor call from the main floor. As shownin FIG. 5 of the above-mentioned patent, the call registering relays areemployed in controlling no-call relays 78, B78, etc. In the presentcase, these relays have added contacts 78-6, B78-6 etc. which will bediscussed below in connection with FIG. 8.

If desired, an up floor lantern may be provided for each car at the mainfloor and a down floor lantern may be provided for each car at the skylobby. These would correspond respectively to the floor lanterns 1UL and6DL of FIG. 5 of the Santini et al. patent and would be similarlyenergized. Other components shown in FIG. 5 of the patent are notrequired for the feeder bank 6.

Although the doors may be operated manually, it will be assumed thatthey are operated as shown in FIG. 6 of the aforesaid Santini et al.patent with one exception. As shown in FIG. 3A break contacts 70T4operated by the non-interference relay 70T are connected in series withthe operating winding of the door-control relay R to prevent closure ofthe doors of the elevator car A for a substantial time such as 5 secondsafter the car stops. The relays QL, Q and DP of the Santini patent arenot required for the feeder bank 0.

FIGURES 4 AND 5 FIGURE 4 reproduces the dispatching circuits of FIG. 7of the aforesaid Santini et al. patent with two changes. In the presentcase, the motor 8ST is continually energized from a source representedby the conductors LACI and LACZ.

The second change relates to the provision of make contacts 02-1 of adown dispatcher expedite relay 02 in shunt with the make contacts 1SD4.As long as the make contacts 021 are open, the dispatcher of FIG. 4dispatches elevator cars from the sky lobby in the same manner as in theaforesaid patent. However, if a predetermined preponderance of trafficis in the up direction from the main floor the make contacts 02-1 closeto expedite the dispatch of additional cars from the sky lobby towardsthe main floor.

It will be understood that the upper terminal relays TT, BTT, CTT andDTT are picked up respectively as long as their associated elevator carsA, B, C and D are respectively at the sky lobby floor.

The remaining components shown in FIG. 7 of the aforesaid patent are nothere required.

FIGURE 5 reproduces circuits employed for dispatching the elevator carsfrom the lower terminal or main floor. These circuits are similar tocircuits shown in FIG. 8 of the aforesaid patent except for thefollowing change.

The only change consists of the addition of make contacts 01-1 in shuntwith make contacts 1SU3. When a substantial preponderance of traffic isin the down direction towards the main floor the contacts 01-1 close toexpedite dispatch of elevator cars from the main floor towards the skylobby.

6 FIGURE 6 FIGURES 6 to 11 introduce a number of new relays. Forconvenience the following list of new relays is included at this point:

01-Up-dispatcher-expedite relay 02Down-dispatcher-expedite relay 0B4,0B3, 0BAL, 0TL4Divisional load relays 0D2, 0D3-D0wn-car relay 011, 012,013, 0I4Load-intensity relays 0P-Period relay 0MGAAuxiliarymotor-generator relay ()QMGl-Surplus-car relay 0QMG2-Deficit-car relay0REAuxiliary sampling relay 0SS1Individual load step relay 0SS2-Bankload step relay GSSB, 0SSTDivisional step relays 0TSampling relay 9U2,0U3-Up-cars relay FIG. 6 shows a cycling system for producing a numberof pulses corresponding to the loading of the elevator car A in the bank0 at the start of each trip of the car.

A similar cycling system is provided for each elevator car of the bank0.

When the elevator car A is stopped at either of its terminal floors, acapacitor 001 is connected in series with a resistor 0R1 and breakcontacts M14 of the running relay M across the direct-current buses L1and L2. The break contacts M14 are added to the running relay M of theaforesaid Santini et al. patent. Consequently, the capacitor is chargedto a voltage dependent on the voltage across the buses.

When the elevator car A starts from the terminal floor at which it isstopped the break contacts M14 open to interrupt the charging circuit ofthe capacitor 0C1. In addition, the make contacts M15 close to connect aperiod relay 0P across the capacitor 0C1 and the resistor 0R1. Thecontacts M15 are added to the running relay M of the above-mentionedpatent. The period relay P picks up and remains picked up for the timerequired for the capacitor 0C1 to discharge through the resistor 0R1and. the relay HP to the dropout voltage of the relay 0P. Consequently,the period relay 0P picks up for a brief period at the start of eachtrip of the elevator car A.

The elevator car A is equipped with a plurality of switches whichindicate different levels of loading of the elevator car. Forillustrative purposes, three load swiches LMS9, LMS10 and LMS11 areprovided and may be operated by the load-measuring switch LMS of theabovementioned Santini et al. patent. To illustrate suitable parameters,the switch LMS9 may be designed to be biased to closed position and tobe opened when the loading of the elevator car reaches 20% of ratedload. The switch LMS10 similarly may open when the loading reaches 50%of the rated load and the switch LMS11 may be designed to open when theloading reaches of rated load.

The three load switches LMS9, LMS10 and LMS11 together with makecontacts 0P3 of the period relay 0P are connected in series between thebus L1 and a first con tact segment located in one level of anindividual load step relay 0551. The second contact segment of thislevel is connected between the switches LMS9 and LMS10. The thirdcontact segment of this level is connected between the switches LMS10,and LMS11. The fourth contact segment of this level is connected betweenthe contacts 6P3 and the switch LMS11.

The step switch @881 may be of convention construction and includes awiper or brush 0SS1B which is stepped successively from a home positioninto engagement with the contact segments 1, 2, 3 and 4 in the level orrow associated with the brush. In addition, the step switch hasself-steeping contacts 088181 and similarly-operated contacts 0SS1S2(FIG. 7) and 058183 (FIG. 9). When the step switch is at rest, theselfstepping contacts SS1S1 are closed. For each step of the stepswitch, the contacts 088181 to 055,153 briefly open and then reclose.Contacts 0SS1S1 are connected in series with the operating winding ofthe step switch 0881 and the make contacts 0P2 of the period relay 0Pacross the buses L1 and L2 to provide a self-stepping circuit for thestep switch.

A homing switch 0SS1H is provided for the step switch 0881. This switchis open when the step switch is in its home position as illustrated inFIG. 6. For all other positions of the steps switch, the homing switch0SS1H is closed. The homing switch is connected in series with breakcontacts 0P1 of the period relay 0P across the make contacts 0P2.

Examples of the operation of the step switch 0851 now will be given. Thecircuits of FIG. 6 indicate that the elevator car A is at rest at aterminal floor and that the capacitor 0C1 is charged. When the elevatorcar A is started from the terminal floor the break contacts M14 open topick up the period relay 0P for a time as above explained. When theperiod relay 0P picks up it opens its break contacts 0P1 to interruptthe homing circuit of the step switch 0581. The make contacts 0P3 closeto connect the contact segments of the step switch to the bus L1.

The make contacts 0P2 close to complete a self-stepping circuit for thestep switch 0881. The first step of this switch carries the brush 0SS1Binto engagement with its first contact segment. During this step theself-stepping contacts 0SS1S1 first open and then reclose.

It will be assumed first that the elevator car A is empty. For thiscondition all of the load switches LMS9 to LMS11 are closed.Consequently, when the brush 0SS1B engages the contact segment 1 of theassociated level a continuous energizing circuit is established for thestep switch which may be traced as follows: L1, 0P3, LMS11, LMS10, LMS9,contact segment 1, brush 0851B, 0851, L2. This circuit holds the stepswitch in the first step position.

At the close of its period, the period relay 0P drops out. The resultantopening of the make contacts 0P2 and 0P3 interrupts the energizingcircuit for the step switch 0881. However the closure of the breakcontacts 0P1 completes a homing circuit for the step switch whichrapidly returns the step switch to its home position.

Let it be assumed next that the elevator car A is loaded to 20% of itsrate of capacity at the time it leaves its terminal floor. The stepswitch 0SS1 steps to its first position in the manner previouslydescribed. However, the load switch LMS9 is now open and the step switchcannot be energized therethrough.

The step switch 0581 now steps to its second position in which the brush0SS1B engages its associated contact segment 2. The operating winding ofthe step switch now is energized through the contacts 0P3 and theswitches LMS11 and LMS to hold the step switch in its second position.During the second step, the self-stepping contacts 0SS1S1 again open andthen close. The step switch remains in its second position until theperiod relay 0P drops out. The step switch then returns to its homeposition in the manner previously described. In this way, the stepswitch for each trip of the elevator car steps a number of timesdependent on the loading of the elevator car.

FIGURE 7 The loadings of the elevator cars of the bank 0 are summed atregular sampling intervals by a step switch 0582 which has two sets ofhoming contacts 0SS2I-I1 and 0SS2H2. These contacts are open when thestep switch is in its home position and are closed when the step switchis away from its home position. The step switch also has a set ofself-stepping contact 08823. These contacts are connected in series withthe operating winding 0552 of the.

step switch, with the homing contacts 0SS2H2 and with make contacts 0RE4of an auxiliary sampling relay 0RE to establish a self-stepping circuitfor the step switch.

The step switch 0552 in addition has a first level or row wiper or brush0SS2B which is connected to the bus L1 through break contacts 0RE5 ofthe auxiliary sampling relay 0RE. The brush coacts with the first leveror row of contact segments which are marked 1 to 40 in FIG. 7. Thecontact segments are associated with four load-intensity relays 011 to014. Pickup of the relay 011 indicates a light loading of the bank 0.Pickup of the relays 012, 013 and 014 respectively indicate moderate,heavy and very heavy loading of the bank 0.

Contact segments 1 to 10 of the first level of the step switch 0852 areconnected to the bus L2 through the lightload-intensity relay 011.Contact segments 11 to 18 are connected to the bus through the operatingwinding of the moderate-load-intensity relay 012. Contact segments 19 to25 are connected to the bus L2 through the operating winding of theheavy-load-intensity relay 013. Contact segments 26 to 40 are connectedto the bus L2 through the operating winding of thevery-heavy-load-intensity relay 014.

When the light-load-intensity relay 0I1 picks up it closes make contacts0I1-1 to establish with three rectifiers 0RR1 to 0RR3 and either breakcontacts 0T3 of a sampling relay 0T or break contacts 0RE6 of theauxiliary sampling relay 0RE a holding circuit. A holding circuit forthe relay 012 is established by make contacts 012-1, the rectifiers 0RR2and 0RR3 and either of the contacts 0T3 or 0RE6. For the relay 013 theholding circuit includes the make contacts 0I31, a rectifier 0RR3 andeither of the sets of contacts 0T3 or 0RE6. Finally, the holding circuitfor the relay 014 includes only the make contacts 0I4-1 and either ofthe sets of contacts 0T3 or 0RE6.

Any suitable timer may be employed for establishing regular samplingperiods for measuring load intensity. In the embodiment illustrated inFIG. 7, a thyratron tube 0TA, preferably of the cold cathode type, hasits plate or anode connected to the bus L1 through the operating windingof the sampling relay 0T and break contacts 0RE2 of the auxiliarysampling relay 0RE. The plate also is connected to the bus L2 throughmake contacts 0T1 of the sampling relay 0T. A capacitor 0C2 is connectedto be charged from the conductors L1 and L2 through a charging resistor0R3 and the break contacts 0RE2 of the auxiliary sampling relay 0RE. Thevoltage across the capacitor is applied between the grid and cathode ofthe thyratron tube 0TA. A discharge resistor 0R2 is connected across thecapacitor 0C2 through make contacts 0RE1 of the auxiliary sampling relay0RE.

In reviewing the operation of the components shown in FIG. 7, it will beassumed that the auxiliary sampling relay 0RE has just dropped out toclose its break contacts 0RE2 thus connecting the capacitor 0C2 and thecharging resistor 0R3 in series across the direct current buses L1 andL2. The capacitor now starts to charge at a rate determined by the sizesof the capacitor and the charging resistor. At the end of apredetermined time, for example, two minutes, the voltage across thecapacitor becomes sufiicient to fire the thyratron tube 0TA and suchfiring r -i sults in energization and pickup of the sampling relay 6When it picks up, the sampling relay closes its holding contacts 0T1 tocomplete with the break contacts 0RE2 a holding circuit for the samplingrelay. In addition, the break contacts 0T3 open to interrupt the holdingcircuits for the load-intensity relays 011 to 014.

If the bank load step relay 0SS2 is in its home position, the homingcontacts 0SS2H1 are open and closure of the make contacts 0T2 of thesampling relay 0T at this timehas no effect on the system. However, ifthe step relay is away from its home position, the contacts 0SS2H1 areclosed and closure of the contacts 0T2 consequently completes anenergizing circuit for the auxiliary sampling relay 0RE.

Pickup of the auxiliary sampling relay 0RE results in closure of itsself-holding contacts 0RE3 which complete a holding circuit through thehoming contacts 0SS2H1.

Consequently, the auxiliary sampling relay remains picked up until thestep switch returns to its home position. In addition, the breakcontacts RE2 open to drop out the sampling relay 0T, and make contacts0RE1 close to establish a discharge circuit for the capacitor 002through the discharge resistor 0R2. Closure of the make contacts 0RE4completes a self-stepping circuit for the step relay 0582 through thehoming contacts 0SS2H2 and the self-stepping contacts 0SS2S.Consequently the step relay now steps to its home position where thecontacts 0SS2H2 open to interrupt the homing circuit. Opening of thebreak contacts 0RE5 disconnects the brush 0SS2-B of the step relay fromthe associated bus L1 to prevent energization therethrough of theload-intensity relays while the step switch is resetting.

Let it be assumed that immediately before the relay 0T picks up thebrush 0SS2B was engaged with the contact segment 19, that all fourload-intensity relays 011 to 014 had been energized during the precedingsampling period and that they were being held in by the break contacts0T3. When the relay 0T picks up, the break contacts 0T3 open tointerrupt the holding circuits for the load-intensity relays. Thisresults in deenergization and drop out of the load intensity relay 014.However, the load-intensity relays 011 and 013 continue to be held inpicked-up condition through the break contacts 0RE5.

Pickup of the sampling relay 0T is followed after a slight time delay bypickup of its auxiliary sampling relay 0RE. The make contacts 0RE6 arearranged to close slightly before the break contacts 0RE5 open.Consequently the holding circuit reestablished by closure of thecontacts 0RE6 now maintains picked up the three load-intensity relays011 to 013. Thus, the load represented by the pickup of these threeload-intensity relays is stored for the duration of the next samplingperiod which is terminated by the next pickup of the sampling relay 0T.

It will be recalled that pickup of the auxiliary sampling relay 0RE isfollowed by drop out of the sampling relay 0T. In dropping out, thesampling relay opens its holding contacts 0T1 to prepare for asubsequent timing operation. In addition, the break contacts 0T3 closeto maintain the holding circuit for any of the load-intensity relayswhich may be picked up at this time. The make contacts 0T2 reopen butthe closed make contacts -0RE3 maintain a holding circuit for theauxiliary sampling relay 0RE until the step relay 0SS2 reaches its homeposition to open the homing contacts 0SS2H1.

During the time required for the capacitor 0C2 to recharge to a voltagesuflicient to again fire the thyratron tube 0TA each car of the feederbank 0 leaving a terminal floor with substantial load supplies pulses tothe step relay 0582. Thus when the elevator car A leaves a terminalfloor, the make contacts 0P4 of the period 0P close for a timesufficient to measure the load in the elevator car. It will be recalledthat during this time the contacts 088182 of the step switch 0881 closeand reopen a number of times dependent on the load carried by theelevator car during this period, and each closure produces a pulse whichadvances the step switch 0582 through one step. Inasmuch as similarpulse circuits are provided for each of the elevators of the bank 0 itfollows that the step switch 0882 is advanced through a number of stepsin each of its sampling periods which corresponds to the total loadcarried by the bank 0 during such period.

It is possible that two or more cars of the bank 0 may apply pulses tothe step relay 0882 at the same time. The probability of the occurrenceof such coincident pulses is small and may be neglected for practicalpurposes. However, if desired, conventional anticoincident circuits maybe employed for assuring the application of one pulse to the step relay0582 for each operation of the contacts 085152 to DOSS1S2.

If the trafiic follows a reasonably regular pattern each day or eachweek the load-intensity relays 011 to 014 may be operated by a timeswitch or clock 0TS. To illustrate such operation, the four switches0SW1 to 0SW4 may be operated to their lower positions as viewed in FIG.7. This connects the load-intensity relays to contacts of the timeswitch fiTS for the purpose of energizing at each instant theload-intensity relays corresponding to the expected load for suchinstant.

FIGURE 8 In FIG. 8 circuits are shown for controlling the number ofelevators in the feeder bank 0 which are in service. If the bank hasmore elevators in service than are required a surplus-car relay 0QMG1picks up to decrease the number of elevator cars in service. If thenumber of elevators in service is insufficient a deficit-car relay 0QDG2picks up to increase the number of elevators in service.

The relays 0QMG1 and 0QMG2 are controlled by a bridge circuit whichincludes five resistors 0R4 and 0R7 to 0R10 connected in series acrossthe direct current buses L1 and L2. Five additional resistors 0R5, 0R6,BOR6, COR6 and DOR6 are connected in series across the buses L1 and L2.Each of the relays 0QMG1 and 0QMG2 is connected in series with aseparate rectifier 0RR4 or 0RR5 between a point located intermediate theresistors 0R4 and 0R7 and a point intermediate the resistors 0R5 and0R6. The resistors 0R4 and 0R5 represent two arms of the bridge. A thirdarm contains the resistors 0R7 to 0R10 in series. The remaining arm ofthe bridge contains the resistors 0R6 to DOR6 in series. The resistors0R4 and 0R5 may have equal resistance values. The remaining resistorseach may have a resistance value equal to one fourth the reistance valueof the resistor 0R4.

The rectifiers 0R4 and 0R5 are oppositely directed. As long as thebridge is balanced both of the relays 0QMG1 and 0QMG2 are dropped outand no change is made in the number of elevators in service. Theresistors 0R7 to 0R10 are shunted respectively by break contacts 011-2to 0I42 of the load-intensity relays. The resistors 0R6 to DOR6 areshunted respectively by break contacts MGS to DMG8 of themotor-generator starting switches for the four elevator cars.

Break contacts MG10 to DMGIO of the four motorgenerator startingswitches are connected in series with an auxiliary motor-generator relay0MGA across the buses L1, L2 through a parallel circuit having four armscontaining respectively break contacts 786 to D78-6 of the no-callrelays 78 to D78.

The operating winding of the motor-generator starting switch MG isconnected across the buses L1 and L2 through make contacts NL8 of thelower-terminal next relay and make contacts 0QMG2-1 of the deficit-carrelay 0QMG2. When the motor-generator starting switch picks up it closesits make contacts MG9 to establish a holding circuit which is completedthrough any one of three sets of contacts; namely, make contacts M16 ofthe running relay M, break contacts NL9 of the lower-terminal next relayand break contacts 0QMG1-1 of the surplus-car relay. Similar circuitsare shown for the motorgenerator starting relay BMG for the elevator Band similar circuits (not shown) are provided for each of the remainingmotor-generator starting relays.

If a call is registered (at least one set of contacts 786 to D78-6 isclosed) while no motor-generator set is running (contacts MG10 to DMG10are closed) the auxiliary motor-generator relay 0MGA picks up to shuntthe contacts 0QMG2-1 to 0QMG2-4 thus permitting starting of a next carto answer the call. Registration of a call is indicated by energizationof one of the floor or car call registering relays of FIG. 3, and by theresultant drop out of one of the no-call relays 78 to D78 in the mannerdiscussed in the above-mentioned patent.

Let it be assumed that the load is'very heavy and that all of theload-intensity relays 011 to 014 are picked up. Let it be assumedfurther that all of the elevators of the feeder bank 0 are in operationand that the motorgenerator starting switches for these elevatorsconsequently are all picked up. Under these circumstances, all of theresistors in the bridge are effectively in circuit and the bridge isbalanced. Therefore, the surplus-car relay QMG1 and the deficit-carrelay 0QMG2 are both dropped out.

Let it be assumed next that the load-intensity drops to a value suchthat the load-intensity relay 014 drops out to close its break contacts014-2 and that the remaining load-intensity relays remain picked up.Under these circumstances the resistor 0R10 is effectively removed fromthe bridge circuit. The bridge now is unbalanced in a direction suchthat the surplus-car relay flQMGl picks up to open the break contactsGQMGl-l in the circuits of the motor-generator starting switch MG of theelevator A and similar contacts located in the circuits for themotor-generator starting switches of the other elevators.

After the pickup of the relay 0QMG1 it will be assumed that the elevatorcar A is selected as the next car to leave the main floor. Under suchcircumstances, the make contacts M16 of the running relay M are open forthe reason that the car has not yet started, The break contacts of thelower-terminal next relay NL9 are open. The make contacts 0QMG2-1 of thedeficit-car relay and the contacts 0MGA1 of the auxiliarymotor-generator relay are open. This interrupts the energization of themotor-generator starting switch MG and this switch drops out to removethe elevator car A from service.

In dropping out, the motor-generator starting switch MG closes its breakcontacts MG8 to effectively remove the resistor 0R6 from the bridgecircuit. The bridge now is restored to balance and the surplus-car relay0QMG1 drops out to reclose its break contacts 6QMG1-1 and similarcontacts for the other cars of the bank. Therefore, no other elevator inthe bank will be removed from service as long as the bridge remains inbalance.

Let it be assumed now that the load-intensity increases until theload-intensity relay 014-2 again picks up to reopen its break contacts0I42. This effectively restores the resistor (R to the bridge. Inasmuchas the motor-generator starting switch MG remains dropped out, the breakcontacts MG8 are still closed and the resistor 0R6 effectively is out ofthe bridge. For these reasons the bridge is unbalanced in the oppositedirection and the deficit-car relay 0QMG2 picks up to close its makecontacts 0QMG2-1 and similar contacts in the circuits of themotor-generator starting switches for the other elevators of the bank.When the elevator car A is again selected as the next elevator car toleave the main floor the make contacts NL8 of the lower-terminal nextrelay NL close to complete an energizing circuit for the motor-generatorstarting switch MG. This restores the elevator A to service. When itpicks up, the motor-generator starting switch MG opens its breakcontacts MG8 to place the resistor 0R6 effectively in the bridge. Thisrebalances the bridge and causes the deficit-car relay 0QMG2 to dropout. This relay thereupon opens its make contacts 0QMG2-1 and similarcontacts associated with the motor-generator starting switches of theremaining cars of the bank.

As shown in the aforesaid Santini et al. patent, the dispatcher for thelower-terminal floor is so arranged that an elevator car at thelower-terminal floor having its motor-generator set in operation isselected as a next car in preference to an elevator car which has itsmotor-generator set shut down. This means that if the elevator A is shutdown at the lower-terminal floor another elevator will have its carselected as the next car to leave the lower-terminal floor unless noother elevator car with its motor-generator set in operation is locatedat the main floor.

FIGURE 9 The divisional index BDI is shown in greater detail in FIG. 9.It comprises a two-way step switch having a first operating winding OSSTand a second operating winding OSSB. Each pulse applied to the windingOSST notches the pointer ()DIP in a clockwise direction for one step.

Each pulse applied to the winding HSSB notches the pointer 0DIP one stepin a counterclockwise direction. Homing contacts OSSH are operated toopen condition only when the pointer BDIP occupies its center positionas indicated in FIG. 9. At its end, the pointer 0DIP has a wiper orbrush which coacts with a level or row of contact segments bearing thenumbers 1 to 19.

The winding 0SSB is connected across the buses L1 and L2 through any oneof four similar parallel circuits one for each of the elevators of thefeeder bank 0. Thus, for the elevator A, the winding OSSB is connectedacross the buses through make contacts W14 of the up-direction relay W,contacts 088153 of the individual-load step relay 0551 and make contacts0P5 of the period relay 0P. Similar circuits are shown for the remainingcars of the bank. Thus during a sampling period, the winding OSSBreceives a number of pulses which corresponds to the loadings of theelevator cars during up trips.

In a similar manner, the winding 0SST receives a number of pulsescorresponding to the loadings of the cars during down trips. Forexample, for the elevator car A, the winding 0SST is connected acrossthe direct-current buses L1 and L2 through make contacts X14 of thedowndirection relay X, contacts 0SS1S3 associated with theindividual-load step relay 0551 and make contacts 0P5 of the periodrelay P. A similar circuit is shown for each of the elevators of thefeeder bank 0.

The sampling period for the divisional index GDI is determined by theauxiliary sampling relay 0RE. This relay has make contacts 0RE7 whichconnect the winding GSSB across the buses L1 and L2 through the homingcontacts (ISSH and the self-stepping contacts 0SSBS. Consequently at theend of each sampling period the contacts 0RE7 close to step thedivisional index 0DI to its home position.

Engagement of the pointer 0DIP with any of the contact segments 1, 2 and3 indicates a heavy preponderant movement of traffic up from the mainfloor. Engagement of the pointer with any of the contact segments 4 to 7indicates a moderate preponderant movement of traffic from the mainfloor in an up direction. Engagement of the pointer with any of thecontact segments 8 to 12 indicates that traffic components leaving thesky lobby and the main floor are substantially equal or balanced.Engagement of the pointer with any of the contact segments 13 to 16indicates a moderate preponderant flow of traflic down from the skylobby. Engagement of the pointer with any of the contact segments 17 to19 indicates a relatively heavy preponderant movement of traflic fromthe sky lobby. Other zone arrangements may be employed if desired.

In many applications, it is desirable to bias the divisional index DI inaccordance with load moved by the local banks towards the sky lobby.Thus each loaded car in the local bank travelling down towards the skylobby may be arranged to supply a predetermined number of pulses to thewinding OSST. In FIG. 9, the winding HSST is additionally connectedacross the buses L1 and L2 through any one of a number of parallelcircuits one for each of the local cars. For the car A in the bank thewinding OSST is connected across the buses through the contacts P1 of aperiod relay P make contacts X14 of a down direction relay X andcontacts LMS8 of a load switch in series. The contacts P1 close for ashort time when the elevator car A of the bank starts down. The contactX14 are closed while the elevator car A of the bank 5 is set for downtravel. The contacts LMS8 are closed while the elevator car A of thebank is loaded to a predetermined extent such as of rated capacity. Ifthe elevator car A of the bank while loaded starts down, a

pulse will be delivered to the winding OSST to actuate the movement ofelevator cars to the sky lobby. In FIG. 9, closure of the contacts B41connects the high call reversal relay HCM for the bank 4: across thebuses L1 and L2. The relay HCM corresponds to the relay HCM of theaforesaid Santini et a1, patent and operates in the same way to expeditemovement of the associated elevator cars to the sky lobby. Contacts ofthe relay 0B4 similarly may control a relay corresponding to the relayHCM for each of the other local banks. A number of controllingcomponents in circuits of the relay HCM as shown in the present FIG. 9and are identified by the same reference characters employed for similarcomponents for the relay HCM in said patent, but preceded by the prefix4).

FIGURE In FIG. 10, divisional load relays 0B4, 0B3, BBAL, 0TL3 and 6TL4are responsive to the relation between trafiic moving up from the mainfloor and traflic moving down from the sky lobby. The pointer 0DIP isconnected to the positive bus L1 through make contacts 0T4 of thesampling relay 0T and break contacts 0RE9 of the relay 0RE. Pickup ofthe relay 6B4 indicates a heavy preponderance of traffic away from themain floor towards the sky lobby. This relay is connected between thenegative bus L2 and the three contact segments 1, 2 and 3 of thedivisional index 0DI when the switch 0SWS is in its upper position.

The relay 0B3 picks up to indicate a moderate preponderance of trafficaway from the main floor towards the sky lobby and is connected betweenthe bus L2 and the contact segments 4 to 7 when the switch 0SW6 is inits upper position.

The relay 0BAL when picked up indicates a substantially balanced trafliccondition. It is connected between the bus L2 and the contact segments 8to 12, when the switch 0SW7 is in its upper position.

When picked up, the relay 0TL3 indicates a moderate preponderance oftraffic from the sky lobby towards the main floor. It is connectedbetween the bus L2 and the contact segments 13 to 16 when the switch6SW8 is in its upper position.

Pickup of the relay 0TL4 indicates a heavy preponderance of traflic fromthe sky lobby towards the main floor. This relay is connected betweenthe bus L2 and the contact segments 17, 18 and 19 when the switch 0SW8is in its upper position.

A holding circuit for the relay 0B4 is established through either breakcontacts 0T5 of the sampling relay 0T or make contacts 0RE8 of theauxiliary sampling relay 0RE, a rectifier 0RR6 and make contacts 0B42. Aholding circuit for the relay 0B3 extends through either the contacts0T5 or the contacts 0RE8, a rectifier 0RR7 and make contacts 0B3-1. Forthe relay 0BAL a holding circuit extends through either the contacts 0T5or the contacts 0RE8, a rectifier HRRS and make contacts 0BAL1. Aholding circuit for the relay 0TL3 extends through the contacts 0T5 orthe contacts 0RE8, a rectifier 0RR9 and make contacts 0TL3-1. For therelay 0TL4, a holding circuit extends through either the contacts 0T5 orthe contacts 0RE8, a rectifier 0RR10 and contacts 6TL4-1.

To illustrate the operation of this circuit, let it be assumed that atthe beginning of the sampling period the relay 0BAL is energized throughthe holding circuit: L1, 6T5, 0RR8, 0BAL1, 0SW7, 0BAL, L2. Let it beassumed further that during the sampling period the pointer 0DIP movesinto engagement with the contact segment 6. At the end of the samplingperiod, the break contacts 0T5 open to deenergize the relay HBAL. Inaddition, the make contacts 0T4 close to complete an energizing circuitfor the relay 0B3. The relay 0B3 then closes its make contacts 0B3-1 toprepare the holding circuit of this relay for subsequent completion.Shortly afterwards, the auxiliary sampling relay BRE picks up to closeits make contacts 0RE8 and thus completes a holding circuit for therelay 0B3. Also break contacts 0RE9 open to prevent false pick 14 up ofa divisional load relay during reset of the two-way step switch. (Thesecontacts could be omitted if the sequence is such that the relay 0Talways drops out before the two-way step switch starts to move at thestart of a resetting operation). The relay 0T then drops out to closeits break contacts 0T5 for the purpose of maintaining the holdingcircuit when the contacts ORES subsequently open. In addition, the makecontacts 0T4 open to disconnect the pointer 0DIP from the bus L1.

If the traffic flow follows a regular pattern from day to day or fromweek to week the relays of FIG. 10 may be operated from a time switch orclock 0TS1. Switches 6SW5 to 6SW9 are provided for the purpose ofswitching the relays to the time switch. When so switched, the timeswitch picks up the proper relay for the proper period of time.

FIGURE 11 In FIG. 11, two up-car relays 0U2 and 0U3 are responsive tothe number of elevators in the feeder bank 0 which are set for uptravel. These relays are connected in parallel for energization throughone or more of four parallel circuits, one for each of the elevators.Thus for the elevator A one of the circuits contains in series makecontacts U8 of the up switch U and a resistor 0R11. It will beunderstood that the make contacts U8 are operated by the up switch U ofthe aforesaid Santini et a1. patent. The resistors 0R11 to DOR11 for thefour elevators have equal resistance values.

The pickup point of the up-car relay 0U2 is adjusted by means. of anadjustable resistor 0R14 which is connected across the operating windingof the relay. For present purposes it will be assumed that the relay isadjusted to pick up when energized through two or more of the resistors0R11 to DOR11. It is dropped out when energized through only one ofthese resistors.

In a similar manner, an adjustable resistor 0R13 is connected across theoperating winding of the up-car relay 0U3 for the purpose of adjustingthe pickup point of this relay. For present purposes, it will be assumedthat this relay picks up when energized through three or more of theresistors 0R11 to DOR11. 'It is dropped out when energized through onlytwo of these resistors.

Various procedures are available for dispatching elevator cars from theterminal floors. For example, an elevator car selected as the next carto leave a terminal floor may be dispatched a predetermined time afterthe preceding car was dispatched, or in dependence on positions of othercars, or under certain load conditions, or in response to assignment toanswer a specific call registration, or after selection. The relays 01and 02 are intended to allocate a proportion of cars in each directionof travel, depending on where the trafiic originates.

The relay 61 may be so arranged that when picked up it permits orexpedites the dispatch of elevator cars from the main floor and whendropped out it prevents the dispatch of cars from the main floor ordelays such dispatch.

In the illustrated embodiment of the invention, the relay 01 has makecontacts 01-1 connected across the make contacts 1SU3 (FIG. 5). Let itbe assumed that traffic is in the balanced range wherein the divisionalload relay 0BAL is picked up. Let it be assumed further that the onlyone elevator car is travelling up. The relay 61 now is picked up andcloses its make contacts 01-1 (FIG. 5 This cuts out the dispatchinginterval at the main floor and the next car at the main floor is startedup provided that its non-interference relay is dropped out to close itsbreak contacts 70T4 (FIG. 3A). As shown in the aforesaid Santini et a1.patent, this relay 70T drops out after a short time delay such as 5seconds measured from the stopping of the associated elevator car at themain floor.

Assuming that the elevator car B has been running up and that the car Ahas just been started up, make contacts U8 and BUS (FIG. 11) are closedand the up'cars relay 0U2 picks up. This relay opens its break contactsU2-1 to deenergize the up dispatcher expedite relay 01 which opens itsmake contacts 011 (FIG. 5) to restore the effectiveness of the contacts1SU3 of the lower-interval holding relay 1SU. Consequently anotherelevator car cannot be started from the main floor until the dispatchinginterval has expired.

Let it be assumed next that traffic conditions are such that thepreponderance of traflic travelling from the sky lobby to the main flooris moderately heavy and that the relay 0TL3 consequently is picked up toclose its contacts 6TL3-2. If we again assume that only one of theelevators cars is traveling up break contacts 0U3-1 of the up-cars relay0U3 is dropped out and the up dispatcher expedite relay 01 is picked upthrough the contacts 0TL3-2 and GUS-1. This'closes the'cont-acts 01-1(FIG. 5) to expedite the dispatch of elevator cars from the main floor.If a second car starts from the main floor, while the first car is stillrunning up, the up-cars relay 0U2 picks up to open its break contacts0U2-ll. This has no immediate effect on the operation of the system.However, if a third car is started from the main floor while the firstand second cars are traveling up, the up-cars relay 0U3 picks up to openits break contacts 0U3-1. This drops out the up dispatcher expediterelay 01 which opens its make contacts 01-1 (FIG. 5) to require asubsequent elevator car at the main floor to wait for its dispatchinginterval before it can be started up. Let it be assumed next that thepreponderance of traffic from the sky lobby to the main floor is veryheavy and that the divisional load relay 6TL4 consequently is picked up.This relay closes its make contacts 0TL4-2 to energize the up dispatcherexpedite relay 01 which closes its make contacts 6L1 (FIG. 5). Elevatorcars are now expedited away from the main floor towards the sky lobbyWhere they are needed until the divisional index operates to deenergizethe divisional load relay 0TL4 to indicate that the heavy down trafiiccondition has subsided.

Similar circuits are provided for controlling the dispatch of elevatorcars from the sky lobby towards the main floor. Thus, down-cars relays0B2 rand 0D3 are connected in parallel for energization through one ormore parallel circuits one for each of the elevator cars. For theelevator car A one of the parallel circuits includes make contacts D8 ofthe down switch D and a resistor 0R15. Adjustable resistors 0R16 and0Rll7 are connected respectively across the operating windings of therelays 0D3 and 0D2 for the purpose of adjusting the pickup points ofthese relays. For illustrative purposes, it is assumed that the relay0D2 is adjusted to pick up when energized through two of the resistorsBRIE to DOR15 and to drop out when energized through only one of theseresistors. The relay 0D3 is arranged to pick up when energized throughthree of these resistors and to be dropped out when energized throughonly two of the resistors.

When the divisional load relay 0BAL is picked up, its make contacts0BAL3 close to energize the down dispatcher expedite relay 02 throughthe break contacts 0D2-1 and 0D3-1. This expedites dispatch of elevatorcars down from the sky lobby in an efiort to make two cars run down inthe same manner by which closure of the make contacts 0BAL2 picked upthe up dispatcher expedite relay 01 to expedite dispatch of elevatorcars from the main floor until two cars were running up as outlinedabove.

If the divisional index registers a moderate preponderant flow oftraffic from the main floor towards the sky lobby, the divisional loadrelay 0B3 picks up to close its make contacts 0B3-2. This energizes thedown dispatcher expedite relay 02 through the contacts OBS-2 and throughthe break contacts ODS-1 of the down cars relay 0D3. The

relay 02 now expedites the dispatch of elevator cars from the sky lobbytowards the main floor where they are needed until three cars set fordown travel pick up the down cars relay 6D3 to open the break contacts0D3-l.

16 This operation is similar to that resulting from closure of the makecontacts 9TL32 which is discussed above for the opposite trafiic fiow.

In the presence of a heavy fiow of trafiic from the main floor towardsthe sky lobby the make contacts 0B4-3 close to pick up the downdispatcher expedite relay 02. This expedites the dispatch of elevatorcars from the sky lobby floor towards the main floor until the downtrafllc flow decreases sufficiently to result in opening of the makecontacts 0B 43.

SUMMARY In summary, the bridge circuit of FIG. 8 compares the number ofcars in service in the feeder bank 0 with the intensity of traific forthe purpose of controlling the surplus-car relay 6QMG1 and thedeficit-car relay OQMGZ. If more cars are in service than are requiredto handle the traffic, the relay 6QMG1 operates to shut down themotorgenerator sets of the surplus elevator cars. Such cars of courseare then available to help out an adjacent feeder bank if required.

If the number of cars in service is insufficient to handle the existingtraffic, the relay HQMGZ picks up for the purpose of startingmotor-generator sets.

The divisional index compares trafiic from the sky lobby to the mainfloor with traffic from the main floor to the sky lobby. The directionand magnitude of the difference is indicated. If desired, trafiictravelling towards the sky lobby in the local banks may modify theregistration of the divisional index. The divisional index is employedfor controlling the allocation of cars in the feeder bank to the skylobby and to the main floor in order to handle traflic most efiiciently.If desired, the divisional index may be utilized to expedite return ofelevator cars in the local banks to the sky lobby under certain trafficconditions.

If the flow of traffic follows a repetitive pattern on a daily or weeklybasis, the number ofelevator cars in service, the allocation of cars tothe sky lobby and the main terminal and the expediting of cars towardsthe sky lobby may be controlled by time clocks or time switches.

We claim as our invention:

1. A conveyor arrangement for a structure having a plurality of landingsincluding a first landing, a third landing displaced from the firstlanding, and a second landing intermediate the first and third landings,said conveyor arrangement having a first conveyor system including avehicle mounted for movement between the first and second landings asterminals for transporting load between the first and second landingsand a second conveyor system including a vehicle mounted for movementbetween the second and third landings for serving said second and thirdlandings, in combination with operating means for moving said vehiclesrelative to the structure to serve said landings, and control meansoperable between a first condition and a second condition, said controlmeans in the first condition coacting with the operating means toprovide a first conveyor service for said landings, and said controlmeans in the second condition coacting with the operating means toprovide a second conveyor service for said landings wherein movement ofthe vehicle in one of said conveyor systems is expedited in apredetermined direction, in combination with expediting means responsiveto a trafiic condition in one of the conveyor systems for modifying saidcontrol means to alter operation of the other of the conveyor systems.

2. An arrangement as claimed in claim 1 wherein said control means inits second condition is effective in the presence of a preponderantdirection of traffic flow for expediting movement of the vehicle in eachof said conveyor systems between said'second landings and a landingspaced from the second landing in a direction opposite to thepreponderant direction of traffic flow.

' 3. A conveyor arrangement for a structure having a plurality oflandings including a first landing, a third land-. ing displaced fromthe first landing, and a second landing intermediate the first and thirdlandings, said conveyor arrangement having a first conveyor systemincluding a vehicle mounted for movement between the first and secondlandings as terminals for transporting load between the first and secondlandings and a second conveyor system including a vehicle mounted formovement between the second and third landings for serving said secondand third landings, in combination with operating means for moving saidvehicles relative to the structure to serve said landings, and controlmeans operable between a first condition and a second condition, saidcontrol means in the first condition coacting with the operating meansto provide a first conveyor service for said landings, and said controlmeans in the second condition coacting with the operating means toprovide a second conveyor service for said landings wherein movement ofthe vehicle in one of said conveyor systems is expedited in apredetermined direction, wherein said control means in the secondcondition expedites movement of the vehicle in the first conveyor systemtowards the second landing, and wherein said control means is operableto a condition for coacting with the operating means to expeditemovement of the vehicle in the second conveyor system towards the secondlanding.

4. An arrangement as claimed in claim 1 wherein the expediting meansincludes with first expediting means responsive to a preponderance oftrafiic flow from said first landing towards said second landing forcoacting with the control means to expedite movement of the vehicle saidsecond conveyor system towards the second landing, and second expeditingmeans responsive to a substantial flow of trafiic in said secondconveyor system towards the second landing for coacting with the controlmeans to expedite movement of the vehicle in said first conveyor systemtowards the second landing.

5. A conveyor arrangement as claimed in claim 1 in combination withtiming means for transferring the control means from one to the other ofsaid conditions at a predetermined time.

6. A conveyor arrangement as claimed in claim 3 in combination withtiming means for transferring the control means from the first conditionto the remainder of the conditions and back to the first condition atpredetermined times.

7. A conveyor arrangement as claimed in claim 1 wherein said firstconveyor system comprises a plurality of vehicles each independentlymovable between the first and second landings, said operating meanscomprises means comprises means for moving each of the vehicles in saidfirst conveyor system between the first and second landings anddispatching means for dispatching each of said last-named vehicles fromeach of said first and second landings a substantial time afterdeparture from the associated landing of a preceding vehicle, and saidcontrol means comprises means effective for said second condition when apreponderance of trafiic desires transportation from one towards theother of the first and second landings for expediting dispatch ofvehicles in the first conveyor system from such other of the first andsecond landings.

8. A conveyor arrangement as claimed in claim 1, wherein the firstconveyor system includes a plurality of vehicles, and wherein saidcontrol means in the second condition allocates to each of the first andsecond landings a number of the vehicles in the first conveyor systemdependent on the proportion of traffic handled by the first conveyorsystem from the associated landing.

9. A conveyor arrangement as claimed in claim 1, wherein said second andthird landings are vertically spaced successively above the firstlanding, and wherein a plurality of additional landings are verticallyspaced between the second and third landings, said first conveyor systemcomprising a plurality of first elevator cars each independently movablebetween the first and second landings, said operating means comprisingmeans for moving each of the first elevator cars between the first andsecond landings, said second conveyor system comprising a plurality ofsecond elevator cars each independently movable between the secondlanding and a plurality of landings located above the second landing,said operating means comprising means for moving each of the secondelevator cars to serve the second landing and a plurality of landingsabove the second landing, said control means being responsive to asubstantial demand for service in one of said conveyor systems towardsthe second landing for expediting movement of elevator cars in the otherof said conveyor systems towards the second landing.

10. A conveyor system as claimed in claim 9 wherein said control meansis responsive to traffic flow in the lastnamed conveyor system away fromthe second landing for expediting movement of elevator cars in thelast-named conveyor system towards the second landing.

11. A conveyor system as claimed in claim 10 in combination with pulsingmeans for each elevator car in one of said conveyor systems forgenerating a number of pulses of a quantity dependent on the loading ofthe associated elevator car, means for counting the total number of saidpulses, and means responsive to said total number for controlling thenumber of elevator cars in the lastnamed conveyor system in service.

12. A conveyor arrangement as claimed in claim 1, wherein said secondand third landings are vertically spaced successively above the firstlanding, and wherein a plurality of additional landings are verticallyspaced between the second and third landings, said first conveyor systemcomprising a plurality of first elevator cars each independently movablebetween the first and second landings, said operating means comprisingmeans for moving each of the first elevator cars between the first andsecond landings, said second conveyor system comprising a plurality ofsecond elevator cars each independently movable between the secondlanding and a plurality of landings located above the second landing,said operating means comprising means for moving each of the secondelevator cars to serve the second landing and a plurality of landingsabove the second landing, said expediting means comprising first trafficmeans responsive to a substantial flow of traflic in the first conveyorsystem towards the second landing for coacting with the control means toexpedite movement of the second elevator cars towards the second landingand to expedite movement of the first elevator cars towards the firstlanding, and second tratfic means responsive to a substantial flow oftrafiic in the second conveyor system towards the second landing forcoacting with the control means to expedite movement of the firstelevator cars towards the second landing, a comparison means forcomparing the number of the elevator cars in operation with the demandfor elevator service in the first conveyor system, and means responsiveto the comparison means for varying the number of the first elevatorcars in operation in accordance with the demand for elevator service.

13. A conveyor arrangement as claimed in claim 12, wherein r saidcomparison means comprises pulse means for generating a number of pulsesof a quantity dependent on car loading for each of the first elevatorcars on each trip, and summing means for repetitively summing saidpulses to indicate the service demand for the first conveyor system, andmeans responsive to the difference between the service demand indicationof said summing means and the number of the first elevator cars inoperation.

14. A conveyor arrangement as claimed in claim 13, wherein said firsttraffic means comprises a divisional index having an index memberoperable in first and second opposing senses, means for operating theindex members in the first sense for each movement of load from thefirst landing by one of the first vehicles, means for operating theindex member in the second sense for each movement 19 of load from thesecond landing by one of the first vehicles, and means responsive to thecondition of the index member for dividing between the first and secondlandings allocations of the first elevator cars in accordance with thedivision in traffic requirements from one to the other of the first andsecond landings.

15. A conveyor arrangement as claimed in claim 14, wherein the secondtraflic means comprises means responsive to predetermined traffic flowin the second conveyor system towards the second landing for operatingthe index member in the second sense.

. References Cited UNITED STATES PATENTS 1? ORIS L. RADER, PrimaryExaminer w. E. ouNcANsoN, IR., AssistantExaminer

